Hello and welcome to the zero to finals podcast. My name is Tom and in this episode I'm going to be

talking to you about fragile X syndrome. If you want to follow along with written notes on this topic,

you can follow along at zero definals.com slash fragile X or in the genetic conditions section of the Zero to Finals Pediatrics book.

So let's get straight into it.

Fragile X syndrome is caused by a mutation in the FMR1 or the Fragile X mental retardation

one gene on the X chromosome.

The FMR1 gene codes for the Fragile X mental retardation 1 gene on the X chromosome. The FMR1 gene codes for the fragile X mental retardation protein,

which plays a role in cognitive development in the brain.

Because the abnormal gene is on the X chromosome, it's an X-linked condition.

However, it's unclear whether it's X-linked dominant or X-linked recessive.

Males are always affected because they only have one X-chromosone,

but females can vary in how much they're affected.

This is because females have a spare normal copy of the fMR1 gene on their other X chromosome.

When the mother is phenotypically normal, meaning that she doesn't have fragile X syndrome,

the affected child may have inherited the X chromosome from their mother,

or the condition may be the result of a de novo or random

mutation in the gene. Let's talk about the features. Fragile X syndrome usually presents with a delay

in speech and language development. Other features are intellectual disability, long, narrow face, large ears, large testicles after puberty,

hypermobile joints, particularly in the hands, attention deficit hyperactivity disorder or ADHD,

autism and seizures. Let's talk about management. There's no cure for the

condition. Management is supportive and involves treating the symptoms. This involves the

multidisciplinary team to support the learning disability, manage the autism and ADHD,

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